Question

A DC current flows through a vertical wire in downward direction. For an observer looking at the wire, the direction of magnetic field at a point between him and the wire is? A) upward b) to the right c) to the left d) downward

Answer 1

to the right flemmings right hand rule if the upper end of the wire is connected to +ve end of battery and lower end is connected to -ve end of battery then direction of magnetic field is in clockwise direction (i,e from right to left) .when upper end is connected to -ve and lower end of wire is connected to -ve terminal of battery then direction of mg.field is anticlockwise (i.e from left to right)